Railway traffic controlling apparatus



April 11, 1939.

B. E. OHAGAN RAILWAY TRAFFIC CONTROLLING APPARATUS Filed Nov. 30, 193'? 2 Sheets-Sheet l 017 Dual (ZED- Selecior Lever SMGII 27 HI 7 KB I M C 6 5 B D N 55 55 4 kg E} [9 2% 1% 1 q 61 B1 C1 40 1 Bgfi X 454 B NFL OR (614 192 7 60 1 18 1 81 45 I a? 242 567: g? '5;

JE/ 54 44 fi 29 28 51 I INVENTOR HIS ATTORNEY Berna E. OHagan April 11, 1939- B. E OHAGAN 2,154,282

RAILWAY TRAFFIC CONTROLLING APPARATUS iled Nov. 30, 1957 2 Sheets-Sheet 2 1115 ATTORNEY Patented Apr. 11, 1939 UNITED STATES PATENT OFFICE RAILWAY TRAFFIC CONTROLLING APPARATUS Application November 30, 1937, Serial No. 177,288

13 Claims.

My invention relates to railway trafiic controlling apparatus, and has for an object the provision of novel and improved apparatus for the control of a railway switch operating motor and for the protection of the switch motor against overload.

I shall describe three forms of apparatus embodying my invention, and shall then point out the novel features thereof in claims.

In the accompanying drawings, Figs. 1, 2 and 3 are diagrammatic views of three dilTerent forms of apparatus, each of which embodies my invention. In each of the several views, like reference characters designate similar parts.

Referring to Fig. 1, a stretch of railway track is formed into a track section IT by the usual insulated rail joints, section IT including a track switch SW. The section IT is provided with a track circuit comprising a battery 2 connected across the rails at one end of the section and a track relay 'I'R connected across the rails at the other end of the section.

The switch SW is actuated by an electric motor M through the medium of a switch operating mechanism SM. The mechanism SM may be oi any standard type and may be of the dual type which includes the usual dual selector lever for selecting between hand operation and motor operation. The mechanism SM is shown conventionally for the sake of simplicity since it forms no part of my present invention. Operatively connected with the switch SW is a controllerH comprising two contacts 3-4 and 5--6, the arrangement being such that contact 3-4 is opened only at the full normal position of the switch, that is, the position illustrated in Fig. 1, and contacts 5-6 is open only at the full reverse position of the switch, that is, the position opposite that illustrated in Fig. l.

The control of the motor M is effected through the medium of a normal contactor NC and a reverse contactor RC, and which contactors are in turn controlled from a. remote point such as an operators ofllce, not shown. In Fig. l, the control of the contactors NC and RC is effected over contacts of relays in a centralized traffic control system of which the relays NWS and RWS are, respectively, the normal and the reverse code switch control relay of a field storage unit. Another relay DR is a relay in the storage unit which is energized during a change from normal switch code to reverse switch code or vice versa. It is deemed sufiicient for this application to point out that relay NWS is energized and picked up in response to a normal switch code and relay RWS such switch code. 5

For providing overload protection for the motor M, the apparatus includes an overload responsive means, several different types thereof being well known in the art. A preferred form of such overload responsive means is shown in Fig. 1 and ,10

comprises a positive temperature coefficient resistor RI connected in multiple with the winding I of an overload relay OR in the motor operating circuit. The overload relay OR in turn controls a pick-up circuit for each of the contactors NC and RC which are also provided with other pickup circuits.

To explain the manner in which the apparatus of Fig. 1 functions, I shall assume that the track section IT is unoccupied, the apparatus is in its normal position as illustrated in Fig. 1 and the operator at the remote station wishes to reverse the position of the switch SW. To reverse the switch SW the operator sends a reverse switch code which causes relay RWS to be picked up and relay NWS to be released, the relay DR being picked up during the reception of such code and then released at the end of such switch code. A pick-up circuit is now formed for the reverse switch contactor RC, this circuit extending from the BI terminal of any convenient source of direct current such as a battery, not shown, over resistor 8, back contact 9 of relay DR, front contact II! of relay RWS, front contact II of track relay TR, contact 5- 6 of controller H, winding of contactor RC and to the CI terminal of the battery. With contactor RC thus energized and picked up, the reverse motor operating circuit is completed from the BI battery terminal over resistor RI and winding 1 of relay OR in multiple, front contact I2 of contactor RC, armature I3 of motor M, back contact I4 of contactor NC, field winding I5 of motor M and to the CI battery terminal. The flow of current in this motor circuit is such as to cause the motor M to be operated in the direction required to move the track switch SW to its reverse position. The parts are so proportioned and adjusted that under the usual prevailing conditions of the track switch the potential drop across the resistor RI is less than a predetermined value and winding 1 of relay OR is not energized sufliciently to pick up the relay OR. Under these usual operating conditions the movement of the track switch is continued until the switch reaches its full reverse position and contact 5-6 is operated to interrupt the circuit for contactor RC, so that contactor RC is deenergized and released to open the motor circuit at the front contact I2 of contactor RC.

To move the track switch SW back to its normal position, the operator could send a normal switch code causing relay NWS to be picked up and relay RWS to be released, the relay DR being picked up during the reception of the switch code and then released. A pick-up circuit for contactor NC is now formed from BI battery terminal over resistor 8, back contact 9 of relay DR, front contact I6 of relay NWS, front contact ll of relay TR, contact 34 of controller H now closed, winding of contactor NC and battery terminal CI, and contactor NC is picked up. Contactor NC on picking up to close its front contact I8 completes the normal motor operating circuit extending from terminal BI over resistor RI and winding I of relay OR in multiple, front contact I8 of contactor NC, motor armature I3, back contact I9 of contactor RC, field winding I5 and battery terminal CI, and the motor M is operated as required to move the track switch from its reverse position to its normal position. Under the usual prevailing operating conditions, the movement is continued until the contact 3--4 is opened at the full normal position of the track switch, causing the contactor NC to be deenergized and released and thereby interrupting the motor circuit at front contact I8.

To explain the manner in which the overload protection for the motor M is accomplished by the apparatus of Fig. l, I shall assume that an obstruction develops in the switch SW while the motor is operating to move the switch to its reverse position, contactor RC being picked up and contactor NC being released. Under this condition, the motor current will rise, heating the resistor RI, raising its resistance. In a short time interval, the resistance of resistor RI reaches a value where the potential drop across the resistor exceeds a predetermined value and the winding I of relay OR is energized sufficiently to pick up relay OR. Relay OR on picking up closes its front contact 20, completing a pick-up circuit for the contactor NC. This circuit involves battery terminal BI, resistor 8, back contact 9 of relay DR, front contact ID of relay RWS, front contact If of relay TR, contact 5-6, front contact 20 of relay OR, winding of contactor NC and battery terminal Cl. Contactor NC now picks up, interrupting the overloaded motor circuit at back contact I4 of contactor NC to protect the motor. The relay OR is, of course, deenergized and released when the overloaded motor circuit is interrupted, but the contactor NC is retained energized over a stick circuit which can be traced from the terminal BI, over resistor 8, back contact 9, front contacts In and II, contact 56, front contact 2I of contactor RC, front contact 22 of contactor NC, winding of contactor NC and battery terminal CI. It follows that both contactors RC and NC are energized and picked up subsequent to the overload and the overloaded motor circuit is held open at the back contact I4 of contactor NC. In order to relieve this situation and regain control of the switch, the operator would send a normal switch code, causing relay NWS to be picked up and relay RWS to be released, the relay DR of the storage unit being picked up during the change. With relay DR picked up to open its back contact 9, the circuits for both contactors NC and RC are interrupted, and both contactors are deenergized and immediately release to their normal deenergized positions. It is to be noted that if the back contact 9 of relay DR were not interposed in the circuits for the contactors NC and RC, these contactors might remain picked up during the change in the switch code due to the fact that front contact I6 of relay NWS might close before the front contact I I] of relay RWS opens, and since both contacts 3-4 and 5-6 of controller H are closed with the switch in mid position. Since both contactors NC and RC are deenergized and released during the change in the switch code, the contactor NC is reenergized in response to the energizing of relay NWS and is picked up to complete the normal switch operating circuit, with the result that the switch is then moved back to its normal position, that is, to the position it occupied prior to the overload condition.

If an obstruction is encountered when the switch is being moved from its reverse position to its normal position, contactor NC being picked up and contactor RC being released, the overload which causes relay OR to be picked up to close its front contact 20 completes a pick-up circuit for the contactor RC. This pick-up circuit involves battery terminal Bl, elements 8, 9, I6, I'I, contact 3-4, front contact 20 of relay OR, winding of contactor RC, and terminal CI. Contactor RC, on pickin up, interrupts at its back contact I9 the overloaded normal motor circuit to protect the motor. Subsequent to the release of the overload relay OR when the overloaded motor circuit is interrupted, the contactor RC is retained energized over a stick circuit extending from terminal BI over the elements 8, 9, IS, IT, contact 3-4, front contact 22 of contactor NC, front contact 2I of contactor RC, winding of contactor RC, and terminal CI. To relieve this situation, the operator would send a reverse switch code, causing relay RWS to be picked up and relay NWS to be released, the relay DR being picked up during the change, with the result that the contactors NC and RC are deenergized and released to their normal positions. With both contactors released, the contactor RC responds to the selection of the relay RWS of the storage unit and picks up to close the reverse motor operating circuit so that the motor is operated to move the switch to the reverse position, that is, to the position it occupied prior to the overload condition.

It is to be pointed out that relay OR and resistor RI are so proportioned and adjusted that starting and reversal surges of current which are of relatively high value do not last long enough to heat resistor RI to the point where relay OR is picked up, Furthermore, the relay OR is preferably provided with slow pick-up characteristics. It is also to be pointed out that occupancy of track section IT shunts the track relay TR, opening its front contacts II and I1, and the control of contactors NC and RC is removed from the relays of the storage unit, the connections to the windings of contactors NC and RC being short-circuited at the back contacts 23 and 24 of track relay TR.

In Fig. l, a contact 25 operated by the dual selector lever is arranged in multiple with front contact 20 of the overload relay OR. Contact 25 is closed when the dual selector lever is reversed and moves the contact 25 to the position indicated by the dotted line. The contact 25 is used to pick up both contactors NC and RC in case the dual selector lever is reversed for hand operation of the switch and the trainman after hand operation leaves the switch in disagreement with the relays of the storage unit. Assuming the relays NWS and RWS are in the position shown and the switch is left in the reverse position subsequent to hand operation so that contact 34 is closed, both contactors NC and RC are picked up. The contactor NC is energized over the pick-up circuit including front contact iii of relay NWS and contact 3-4. The contactor RC is picked up over the circuit including front contact 16 of relay NWS, contact 3-4, contact 25 in its closed position and winding of contactor RC, since the contact 25 is closed during the interval between the time the trainman positions the switch in the reverse position and the time he places the selector lever to its normal position. With contactor RC thus picked up, it is retained energized over its stick circuit subsequent to the restoring of the selector lever to its normal position to open contact 25, with the result that both contactors are energized and further operation of the switch is prevented. Under these circumstances, it is necessary for the operator to send a reverse switch code so as to change the position of the relays of the storage unit, the contactors being deenergized and released to their normal deenergized positions while relay DR is picked up. Subsequent to such operation, the contactors NC and RC respond to the new position of the relays of the storage unit and the switch is moved to a position to agree with the position of the relays of the storage unit.

With the apparatus constructed as shown in Fig. l, circuit cross protection is obtained because, if, when the apparatus is in the normal position and a cross should occur in the connection leading to the winding of contactor RC which might cause that contactor to be picked up to start a movement of the motor, the contact 3-4 of controller H would first be closed and complete a circuit for the contactor NC, and contactor NC would be picked up. With both contactors picked up, the circuit for the motor M would be interrupted and further operation of the switch SW would be avoided.

Fig. 2 discloses circuits whereby this contactor control and overload protection to a railway switch motor embodying my invention may be applied to a standard interlocking machine. In Fig. 2, the switch SW is actuated by the motor M through a switch operating mechanism SM, the same as in Fig. 1. The operating circuits for motor M are controlled by the normal contactor NC and the reverse contactor RC, together with a contactor BC to be referred to later. In Fig. 2, the overload protection means consists of a resistor RI and the winding 7 of the overload relay OR, the same as in Fig. 1. The controller H of Fig. 2 is also similar to the controller H of Fig. 1. The contactors NC and RC of Fig. 2, as well as the contactor BC, are controlled over the switch control lever L of an interlocking machine. The lever L is provided with the usual five positions, normal, normal indication, center, reverse indication, and reverse, these positions being indicated respectively by the reference characters N, B, C, D and R. The lever L actuates two contact members .30 and 3|, the function of which will later appear.

In Fig. 2, the relay KR is the usual switch indication relay, relay KR being governed over the usual indication circuit including pole changer contacts 26 and 21 operated from the switch SW, as indicated by a dotted line. In

order to check that the contactors NC and RC have returned to theirnormal deenergized positions subsequent to operation of the switch, the indication circuit for relay KR is completed over back contacts 28 and 29 of contactors RC and NC, respectively, as will be readily understood by an inspection of Fig. 2.

To describe the manner in which the apparatus of Fig. 2 functions, I shall first take up the operations which follow when the operator moves the lever L to its reverse indication position D for the purpose of causing the switch to be moved to its reverse position. With lever L moved to its D position, two circuits are completed, one for the contactor BC and one for the contactor RC. The circuit for the contactor BC involves battery terminal Bl, lever contact 3ll32, front neutral contact 33 of relay KR, normal polar contact 34 of relay KR, line wire 35, winding of contactor BC and terminal CI, and contactor BC is energized, raising its contact 36 to the position indicated by the dotted line to prepare the motor operating circuit at this point. The circuit for the contactor RC involves battery terminal Bl, I

lever contact 3I-3'|, line wire 38, contact 5-6,

winding of contactor RC and terminal Cl, and contactor RC is picked up to complete the reverse motor circuit at its front contact 12. The reverse motor operating circuit is the same as in Fig. 1, except to include contact 36 of the contactor BC. Under usual operating conditions,

the reverse movement of the switch continues until the full reverse position is reached, where contact 5--6 is opened to deenergize contactor RC, which contactor upon releasing interrupts at its front contact I2 the reverse motor operating circuit. With the switch moved to its reverse position, the pole changer contacts 26 and 21 are reversed and the usual reverse indication circuit for the relay KR is completed and relay KR is energized by current of reverse polarity, this indication circuit being completed, however, only if both contactors RC and NC are released to close their respective back contacts 28 and 29. It is to be pointed out that while the switch is in mid stroke the relay KR is deenergized due to the mid-stroke position of contacts 26 and 21, but the contactor BC is retained energized over the back contact 39 of relay GR. When, however, relay KR is energized with current of reverse polarity, the circuit by which the contactor BC is energized is interrupted at the normal polar contact 34 of relay KR and contactor BC is restored to its normal deenergized position. Relay KR will, of course, govern the usual indication magnets associated with the switch lever L, but which magnets are not shown since they form no part of my present invention.

In case the operator desires to restore the switch SW to its normal position, and to that end moves the lever L to its normal indication position B, two circuits are completed, one for the contactor BC and the other for the contactor NC. The circuit for the contactor BC this time extends from terminal Bl over lever contact 30-40, front contact 4| and reverse polar contact 42 of relay KR, line wire 35, winding of contactor BC and terminal Cl, and contactor BC is energized to close contact 36, the same as before. This circuit for contactor NC extends from terminal BI, over lever contact 3l-43, line wire 44, contact 3-4, winding of contactor NC and to the terminal Cl, and contactor NC is picked up to complete the normal motor operating circuit at its front contact l8. Under ordinary opcrating conditions, the movement of the switch to its normal position is continued until the contact 34 is opened at the full normal position to deenergize contactor NC and interrupt the motor operating circuit at front contact 18. The pole changer contacts 25 and 21 are now moved to their normal positions, as illustrated by the solid lines in Fig. 2, and the normal indication circuit for relay KR is formed and relay KR is energized with current of normal polarity, the circuit being completed only if contactors NC ann BC are both deenergized to close the respective back contacts 29 and 28. This time, the contactor BC is retained energized during mid-stroke position of the switch over back contact 45 of relay KR, and is then deenergized and released when relay KR is shifted to its normal position to open the reverse polar contact 42.

If, in either movement of the switch in Fig. 2, an overload condition occurs, the resistor RI heats up, with the result that relay OR is picked up when the potential drop across resistor RI exceeds the predetermined value. Relay OR of Fig. 2, on picking up to close its front contact 20, completes a pick-up circuit for the deenergized contactor NC or RC, as the case may be, and that contactor is energized and picked up so that the overloaded motor circuit is interrupted and the movement stopped. The pick-up circuits controlled by relay OR for energizing the contactors NC and RC are the same as in Fig. 1 and need i not be repeated. The contactors NC and RC of Fig. 2 are provided with stick circuits, the same as in Fig. l and it is thought that they need not be described again in detail.

It is clear that the apparatus of Fig. 2 provides the same protection as the apparatus of Fig. 1 in case of a circuit cross. If a cross occurs on the connection leading to the contactor RC when the switch is normal, the contactor NC is also picked up as soon as the controller H is moved to close the contact 3-4, and contactor NC, on picking up, interrupts the motor circuit to stop further operation. In case the switch occupies its reverse position and a cross occurs on the connection leading to the contactor NC, the reverse contactor RC is energized as soon as the controller H is shifted to close contact 5-5, and contactor RC, on picking up, interrupts the mtor circuit. The contactor BC is used to provide additional protection, but may be omitted if desired.

Fig. 3 shows apparatus in which the switch controlling contactors are controlled through the medium of a polarized relay WR, and the overload protection is accomplished. by providing the contactors NCI and RCI, each with a separate winding which is interposed in a motor operating circuit in multiple with a resistor having a positive temperature coefiicient. The polarized relay WR is controlled over a pole changer PC which may be located at any convenient point such as the operators office.

It is believed that the apparatus of Fig. 3 can best be understood by a description of its operation. I shall assume that the operator desires to reverse the switch and to that end reverses the pole changer PC to its dotted line position so that the relay WR is energized by current of reverse polarity and its polar contact 65 is shifted to the right-hand position, as viewed in Fig. 3. A control circuit is formed from the terminal Bl over front neutral contact 46 and polar contact 65 in its reverse position, line wire 41, front contact 48 of track relay TR, contact -6 of controller H, top winding 49 of the reverse contactor RC! and to the terminal Cl, and contactor RCI is picked up. Contactor RCI, when energized and picked up, completes the reverse motor operating circuit which extends from terminal BI over winding 50 of the normal contactor NCI and resistor R2 in multiple, front contact 5| of contactor RCI, motor armature l3, back contact 52 of contactor NCI, field winding l5 and terminal Cl. This reverse motor operating circuit is effective to operate motor M as required to move the track switch to its reverse position, contact 5--5 being moved to its open position at the full reverse position of the switch to cause contactor RCI to become deenergized. Contactor RCI, when denergized and released, interrupts the motor circuit at front contact 5|.

The winding 50 of contactor NCI and resistor R2 are so proportioned and adjusted that the usual motor operating current flowing in the reverse operating circuit does not cause contactor NCI to pick up, but that an overload current causes resistor R2 to heat up and shortly raise its resistance to a point where the current shunted through winding 50 of contactor NCI is suflicient to pick up that contactor, interrupting the overloaded motor circuit at back contact 52 of contactor NCI. With contactor NCI picked up, a stick circuit is completed which is the same as the control circuit for contactor RCI up to the upper right-hand terminal of contactor RCI, thence over front contact 53 of contactor RCI, front contact 54 of contactor NCI, winding 55 of contactor NCI and terminal C l It follows that both contactors NCI and RCI are retained picked up subsequent to an overload condition of the reverse motor operating circuit to hold the overloaded circuit open. To regain control of the switch, the operator must shift the pole changer PC to reverse the relay WR. With the energization of relay WR reversed, the front neutral contact 46 is opened during the period the magnetic flux of relay WR is passing through zero, with the result that both contactors N Cl and RC! are deenergized and released to their normal deenergized positions.

With relay WR reenergized in its normal position, a circuit for the contactor NCI is formed. This circuit can be traced from terminal Bl over front contact 46 and polar contact 55 in its lefthand position, wire 56, front contact 51 of relay TR, contact 3-4 now closed, winding 55 of normal contactor NCI and to terminal Cl, and contactor NCI is picked up to complete the normal motor circuit. The normal motor circuit extends from terminal Bl over winding 58 of contactor RCI and resistor R3 in multiple, front contact 59 of contactor NCI, motor armature l3, back contact 60 of contactor RCI, field winding I5 and terminal Cl, and the motor M is operated as required to move the switch to its normal position. At the full normal position of switch SW, the contact 3-4 is opened causing contactor NCI to become denergized and released, opening the normal motor circuit at its front contact 59, the winding 58 of contactor RC1 and resistor R3 are so proportioned that the usual current flowing in the normal motor operating circuit is not effective to energize the contactor RCI, but that an overload current causes resistor R3 to heat up so that the current shunted through winding 58 is suflicient to energize the contactor R0! to pick up that contactor. Contactor RCI upon picking up is operated to interrupt the overloaded motor circuit at its back contact 50, and

completes a stick circuit by which it is retained energized. This stick circuit for contactor RCI is the same as the control circuit for contactor NCI up to the upper left-hand terminal of winding 50 of contactor NCI; thence over front contacts 54 and 53 and winding 49 of contactor RCI, with the result that both contactors are retained energized subsequent to an overload condition. To restore the apparatus and regain control of the switch, the operator must shift the pole changer PC to its reverse position and energize the relay WR with current of reverse polarity. During the interval the contact 46 is open as the magnetic flux passes through zero both contactors NCI and RCI are restored to their normal deenergized positions. Contacto-r RCI will now respond to the reverse position of relay WR and cause the motor M to restore the switch to its reverse position, that is, the position it occupied prior to the overload.

It is clear that the storage relay control of Fig. 1 may be used in place of the lever control of Fig. 2 or the polarized relay control of Fig. 3; also that the control of Fig. 2 may be used with the apparatus of either Fig. 1 or 3; and the control by a polarized relay of Fig. 3 may be substituted for the control shown in Figs. 1 and 2.

Although I have herein shown and described only three forms of apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In combination, a railway switch operating motor, a normal and a reverse contactor, a normal motor operating circuit including a front contact of said normal contractor and a back contact of said reverse contactor, a reverse motor operating circuit including a front contact of said reverse contactor and a back contact of said normal contactor, a pick-up circuit for each of said contactors including a remote controlled contact, a control means for selectively closing either one or the other of said remote controlled contacts to energize either the normal or the reverse contactor, overload means associated with said motor operating circuits effectively infiuenced when current above a predetermined value flows in either motor circuit for a given interval, means governed by said overload means when effectively influenced to energize the contactor which is deenergized at the time of the overload, and a stick circuit for each contactor including the remote controlled contact associated with the other contactor.

2. In combination, a railway switch operating motor, a normal and a reverse contactor, a normal motor operating circuit including a front contact of said normal contactor and a back contact of said reverse contactor, a reverse motor operating circuit including a front contact of said reverse contactor and a back contact of said normal contactor, control means operative to energize either the normal or the reverse contactor for reversibly operating the motor, overload means associated with said motor operating circuits effectively influenced when current above a predetermined value flows in either motor circuit for a given interval, means governed by the overload means when effectively infiuenced to energize the deenergized contactor at the, time of the overload for interrupting the overloaded motor circuit, and stick circuit means governed by said control means and including a front contact of each of said contactors for holding the overloaded circuit open.

3. In combination, a railway switch operating motor, a normal and a reverse contactor, a normal motor operating circuit including a front contact of said normal contactor and a back contact of said reverse contactor, a reverse motor operating circuit including a front contact of said reverse contactor and a back contact of said normal contactor, control means operative to either a first or a second position for respectively energizing the normal and reverse contactors to reversibly operate the motor, overload means associated with said motor operating circuits effectively influenced when current above a predetermined value fiows in either motor circuit for a given interval, a first circuit controlled by the overload means when effectively influenced and the second position of the control means to energize the normal contactor, a second circuit controlled by the overload means when effectively influenced and the first position of the control means to energize the reverse contactor,

a stick circuit for the normal contactor governed by the second position of the control means and its own front contact, and a stick circuit. for the reverse contactor governed by the first position of the control means and its own front contact.

4. In combination, a railway switch operating motor, a normal and a reverse contactor, a normal motor operating circuit including a front contact of said normal contactor and a back conth normal position of the switch and a second means governed by the overload means to energize the reverse contactor when overload current flows in the normal motor circuit for a given interval, means governed by the overload means to energize the normal contactor when overload current flows in the reverse motor circuit for a given interval, a stick circuit for the normal contactor including the second position of the control means and said second controller contact, and a stick circuit for the reverse contactor including the first position of the control means and said first controller contact.

5. In combination, a railway switch operating motor, a normal and a reverse contactor, a normal motor operating circuit including a front contact of said normal contactor and a back contact of said reverse contactor, a reverse motor operating circuit including a front contact of said reverse contactor and a back contact of said normal contactor, a controller operated by the switch having a first contact open only at the normal position of the switch and a second contact open only at the reverse position of the switch, control means having a first and a second position, a pick-up circuit for the normal contactor including the first position of said control means and said first controller contact, a pick-up circuit for the reverse contactor including the second position of said control means and said second controller contact, overload means associated with said motor operating circuits, means governed by the overload means to energize the reverse contactor when overload current flows in the normal motor circuit for a given interval, means governed by the overload means to energize the normal contactor when overload current flows in the reverse motor circuit for a given interval, a stick circuit for the normal contactor including the second position of the control means and said second controller contact as well as a front contact of each of said contactors, and a stick circuit for the reverse contactor including the first position of said control means and said first controller contact as Well as a front contact of each of said contactors.

6. In combination, a railway switch operating motor, a normal and a reverse contactor, a normal motor operating circuit including a front contact of said normal contactor and a back contact of said reverse contactor, a reverse motor operating circuit including a front contact of said reverse contactor and a back contact of said normal contactor, a pick-up circuit for each of said contactors including a remote controlled contact, control means for selectively closing either one or the other of said remote controlled contacts to energize either the normal or the reverse contactor, overload means associated with said motor operating circuits characterized by a positive temperature coeificient, circuit means governed by said overload means to energize the reverse contactor in response to an overload of the normal motor circuit, other circuit means governed by the overload means to energize the normal contactor in response to an overload of the reverse motor circuit, a stick cir cuit for the reverse contactor including the remote controlled contact associated with the pickup circuit for the normal contactor, and a stick circuit for the normal contactor including the remote controlled contact associated with the pick-up circuit for the reverse contactor.

7. In combination, a railway switch operating motor, a normal and a reverse contactor, a normal motor operating circuit including a front contact of said normal contactor and a back contact of said reverse contactor, a reverse motor operating circuit including a front contact of said reverse contactor and a back contact of said normal contactor, a positive temperature coeiiicient resistor common to both of said motor circuits, an overload relay having a winding connected across said resistor to pick up said relay only when an overload current flows through said resistor, control means including pick-up circuits for said contactors for reversibly operating said motor, other pick-up circuit means for said contactors including a front contact of the overload relay for picking up the deenergized contactor in the event of an overload on a motor circuit to interrupt the overloaded circuit, and stick circuit means including a front contact of each of said contactors to retain picked up the last energized contactor for holding the overloaded circuit open.

8. In combination, a railway switch operating motor, a normal and a reverse contactor, a normal motor operating circuit including a front contact of said normal contactor and a back contact of said reverse contactor, a reverse motor operating circuit including a front contact of said reverse contactor and a back contact of said normal contactor, a positive temperature coetficient resistor common to both of said motor circuits, an overload relay having a winding connected across said resistor to pick up said relay only when an overload current flows through said resistor, a first pick-up circuit for each contactor including a remote controlled contact, means for closing either one or the other of said remote controlled contacts for selectively energizing the contactors, a second pick-up circuit for each contactor including a front contact of the overload relay and the remote controlled contact associated with the other contactor, and a stick circuit for each contactor including its own front contact and the remote controlled contact associated with the other contactor.

9. In combination, a railway switch operating motor, a normal and a reverse contactor, a normal motor operating circuit including a front contact of said normal contactor and a back contact of said reverse contactor, a reverse motor operating circuit including a front contact of said reverse contactor and a back contact of said normal contactor, a positive temperature coefficient resistor common to both of said motor circuits, an overload relay having a winding connected across said resistor to pick up said relay only when an overload current flows through said resistor, a first pick-up circuit for each contactor including a remote controlled contact and a normally closed contact which is common to both of said pick-up circuits, control means for selectively closing either one or the other of said remote controlled contacts for selectively energizing either the normal or the reverse contactor, a second pick-up circuit for each contactor including a front contact of said overload relay, a stick circuit for each contactor including said normally closed contact and the re mote controlled contact associated with the other contactor as well as its own front contact, and means governed by said control means to open said normally closed contact when changing the selection of the remote controlled contacts.

10. In combination, a railway track switch, a switch operating mechanism of the dual selector type connected with said switch, a reversible motor for actuating said mechanism, a normal and a reverse contactor, a normal motor circuit in cluding a front contact of the normal contactor and a back contact of the reverse contactor, a reverse motor circuit including a front contact of the reverse contactor and a back contact of the normal contactor, remote controlled means having a first and a second position for energizing respectively the normal and reverse contactors, a normally open contact actuated by the dual selector to a closed position when the switch mechanism is set for hand operation, pick-up circuit means controlled in part by said normally open contact to energize both of said contactors when the switch is left is disagreement as to position with said remote controlled means, a stick circuit for said normal contactor including the remote controlled means in its second position, and a stick circuit for the reverse contactor including the remote controlled means in its first position.

11. In combination, a railway track switch, a motor for actuating said switch, a pole changer operatively connected with the switch, a normal and a reverse contactor as well as another contactor, a normal motor operating circuit includcircuit including the normal indication position of said lever and a reverse polar contact of said relay to energize said other contactor, a second pick-up circuit including the normal indication position of the lever to energize said normal contactor, a third pick-up circuit including the re verse indication position of said lever and a normal polar contact of said relay to energize said other contactor, a fourth pick-up circuit including the reverse indication position of said lever to energize said reverse contactor, and an indication circuit to control said relay including said pole changer and a back contact of each of the normal and reverse contactors. 12. In combination, a railway switch operating motor, a normal and a reverse contactor each provided with a first and a second winding, a first and a second resistor each having a positive temperature coeflicient, a normal motor operating circuit including the second resistor and second winding of the reverse contactor in multiple and a front contact of the normal contactor as well as a back contact of the reverse contactor, a reverse motor operating circuit including the first resistor and second winding of the normal contactor in multiple and a front contact of the reverse contactor as well as a back contact of the normal contactor, control means operative to a first and a second position to energize the first winding of the normal contactor and the first winding of the reverse contactor respectively, a stick circuit for the normal contactor including the second positon of said control means, and a stick circuit for said reverse contactor including the first position of said control means.

13. In combination, a railway switch operating motor, a normal and a reverse contactor each provided with a first and a second winding, a normal motor operating circuit including the second winding of the reverse contactor and a front contact of the normal contactor as well as a back contact of the reverse contactor, a reverse motor operating circuit including the second winding of the normal contactor and a front contact of the reverse contactor as well as a back contact of the normal contactor, control means having a first and second positon, a first pick-up circuit including the first position of the control means and the first winding of the normal contactor, a second pick-up circuit including the second position of the control means and the first winding of the reverse contactor, a stick circuit for the normal contactor including the second position of the control means as well as the first winding and a front contact of the normal contactor, and a stick circuit for the reverse contactor including the first position of the control means as well as the first winding and a front contact of the reverse contactor.

BERNARD E. OHAGAN. 

